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Sterigmatocystin (STC) and 5-methoxysterigmatocystin (5-M-STC) are mycotoxins produced by common damp indoor Aspergilli series Versicolores. Since both STC and 5-M-STC were found in the dust of indoor occupational and living areas, their occupants may be exposed to these mycotoxins, primarily by inhalation. Thus, STC and 5-M-STC were intratracheally instilled in male Wistar rats using doses (0.3 mg STC/kg of lung weight (l.w.); 3.6 mg 5-M-STC/kg l.w.; toxin combination 0.3 + 3.6 mg/kg l.w.) that corresponded to concentrations detected in the dust of damp indoor areas in order to explore cytotoxicity, vascular permeability, immunomodulation and genotoxicity. Single mycotoxins and their combinations insignificantly altered lactate-dehydrogenase activity, albumin, interleukin-6, tumor necrosis factor-α and chemokine macrophage inflammatory protein-1α concentrations, as measured by ELISA in bronchioalveolar lavage fluid upon 24 h of treatment. In an alkaline comet assay, both mycotoxins provoked a similar intensity of DNA damage in rat lungs, while in a neutral comet assay, only 5-M-STC evoked significant DNA damage. Hence, naturally occurring concentrations of individual STC may induce DNA damage in rat lungs, in which single DNA strand breaks prevail, while 5-M-STC was more responsible for double-strand breaks. In both versions of the comet assay treatment with STC + 5-M-STC, less DNA damage intensity occurred compared to single mycotoxin treatment, suggesting an antagonistic genotoxic action.  相似文献   
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The inflammatory milieu favors recruitment and activation of osteoclasts, and leads to bone destruction as a serious complication associated with arthritis and with other inflammatory processes. The frequency and activity of osteoclast progenitors (OCPs) correspond to arthritis severity, and may be used to monitor disease progression and bone resorption, indicating the need for detailed characterization of the discrete OCP subpopulations. Collectively, current studies suggest that the most potent murine bone marrow OCP population can be identified among lymphoid negative population within the immature myeloid lineage cells, as B220?CD3?CD11b–/loCD115+CD117+CX3CR1+ and possibly also Ter119?CD11c?CD135loLy6C+RANK?. In peripheral blood the OCP population bears the monocytoid phenotype B220?CD3?NK1.1?CD11b+Ly6ChiCD115+CX3CR1+, presumably expressing RANK in committed OCPs. Much less is known about human OCPs and their regulation in arthritis, but the circulating OCP subset is, most probably, comprised among the lymphoid negative population (CD3?CD19?CD56?), within immature monocyte subset (CD11b+CD14+CD16?), expressing receptors for M-CSF and RANKL (CD115+RANK+). Our preliminary data confirmed positive association between the proportion of peripheral blood OCPs, defined as CD3?CD19?CD56?CD11b+CD14+, and the disease activity score (DAS28) in the follow-up samples from patients with psoriatic arthritis receiving anti-TNF therapy. In addition, we reviewed cytokines and chemokines which, directly or indirectly, activate OCPs and enhance their differentiation potential, thus mediating osteoresorption. Control of the activity and migratory behaviour of OCPs as well as the identification of crucial bone/joint chemotactic mediators represent promising therapeutic targets in arthritis.  相似文献   
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While most drugs of abuse increase dopamine neurotransmission, rapid neurochemical measurements show that different drugs evoke distinct dopamine release patterns within the nucleus accumbens. Rapid changes in dopamine concentration following psychostimulant administration have been well studied; however, such changes have never been examined following opioid delivery. Here, we provide novel measures of rapid dopamine release following intravenous infusion of two opioids, morphine and oxycodone, in drug‐naïve rats using fast‐scan cyclic voltammetry and rapid (1 min) microdialysis coupled with high‐performance liquid chromatography ‐ tandem mass spectrometry (HPLC‐MS). In addition to measuring rapid dopamine transmission, microdialysis HPLC‐MS measures changes in GABA, glutamate, monoamines, monoamine metabolites and several other neurotransmitters. Although both opioids increased dopamine release in the nucleus accumbens, their patterns of drug‐evoked dopamine transmission differed dramatically. Oxycodone evoked a robust and stable increase in dopamine concentration and a robust increase in the frequency and amplitude of phasic dopamine release events. Conversely, morphine evoked a brief (~ 1 min) increase in dopamine that was coincident with a surge in GABA concentration and then both transmitters returned to baseline levels. Thus, by providing rapid measures of neurotransmission, this study reveals previously unknown differences in opioid‐induced neurotransmitter signaling. Investigating these differences may be essential for understanding how these two drugs of abuse could differentially usurp motivational circuitry and powerfully influence behavior.  相似文献   
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We hypothesized that patients with sepsis and AKI, especially patients without preserved renal function, and treated with continuous veno-venous hemodiafiltration (CVVHDF), have lower risk for mortality than patients treated with continuous veno-venous hemofiltration (CVVH). Patients were included if they fulfilled the diagnosis of severe sepsis or septic shock, suffered AKI and received continuous renal replacement therapy (CRRT) in intensive care unit. There were 62 patients treated by CVVH and 75 treated by CVVHDF. Mean survival time was longer in CVVHDF group with oliguric/anuric patients than in CVVH group. CVVH, and not classic risk factors, was associated with higher overall mortality in oliguric/anuric patients. In the linear regression model, hourly urine output was the strongest and positive predictor of longer survival. CVVHDF is according to our results a CRRT modality of choice for the treatment and lower mortality of septic patients with AKI where renal function is no longer preserved. CRRT has been associated with improved renal recovery, but it should be started earlier in AKI evolution with still preserved hourly urine output which is the most sensitive and prognostic marker of survival in septic patients with AKI.  相似文献   
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Purpose. The present paper tries to address the rise and decay of the sea-water “cult” in regional health tourism in NW Croatia, concentrating upon and analysing more thoroughly the example of Marina, chemicaly processed sea water, an invention of Dr Géza Fodor, the Hungarian physician practicing in that part of Croatia.

Method. The original documents and archived items related to the topic were examined. Furthermore, we investigated numerous comunal bulletins and medical authorities' records of respective time.

Results. Our research showed that the sea-water baths, introduced thanks to the influence of balneologists (like J. Glax), and “drinking cures” (advocated by M.-J. Örtel, for instance) were surprisingly popular not only among tourists of the time, but also among the physicians that used them extensively for therapeutical purposes. These baths and “drinking cures” enriched and completed the medical offer of the resorts regardless of their sometimes dubious effectiveness.

Conclusions. This simple distilled sea-water preparation, advertised as a real panacea, demonstrates a paradigm that elucidates the mentality of physicians, merchants, and patients/consumers of the time.  相似文献   
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Early experiences exert their effects on adult parental behavior in part by altering the development of neurobiological mechanisms that initiate or support the initiation and sustenance of adult parental behavior. The effects of parental behavior on sensory, perceptual and emotional mechanisms in offspring constitute an experientially based mechanism by which neurobiological factors regulating behavior can be transferred from generation to generation somewhat independently of genetic endowment.  相似文献   
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Rationale Repeated exposure to psychomotor stimulants can lead to sensitization to their effects, and sensitization has been implicated in the pathophysiology of schizophrenia and drug abuse. These disorders are characterized by cognitive deficits, particularly in prefrontally mediated executive function.Objective The present experiments were conducted to investigate the effects of sensitizing regimens of amphetamine and phencyclidine (PCP) on attentional set shifting.Methods Rats received injections of amphetamine, PCP or saline three times per week for 5 weeks. Four weeks later, rats were trained to dig for food in one of two bowls, each bowl having an odour and a texture. Only one dimension (odour or texture) correctly predicted which bowl was baited. Rats were then tested on a series of discriminations including those requiring an intra-dimensional shift (IDS), an extra-dimensional shift (EDS) or a reversal of previously relevant and irrelevant stimuli.Results Rats sensitized to amphetamine performed normally on the IDS, but were impaired on the EDS, as well as on reversal discriminations. PCP-sensitized rats were unaffected on any of the discriminations. In amphetamine-sensitized rats the deficit at the EDS stage was reversed by infusion of the D1 receptor agonist SKF38393 into the medial prefrontal cortex (mPFC).Conclusions Results show that the amphetamine-sensitized state impairs prefrontally mediated attentional set shifting. This is consistent with cognitive deficits in schizophrenia and addiction, and with the evidence that amphetamine sensitization is accompanied by functional changes in the mPFC. These results further add to a growing literature showing that activating D1 receptors in the mPFC improves aspects of cognition.  相似文献   
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